Related papers: The mass and temperature functions in a moving bar…
We use N-body simulations to find the effect of neutrino masses on halo properties, and investigate how the density profiles of both the neutrino and the dark matter components change as a function of the neutrino mass. We compare our…
We measure the clustering of dark matter halos in a large set of collisionless cosmological simulations of the flat LCDM cosmology. Halos are identified using the spherical overdensity algorithm, which finds the mass around isolated peaks…
A luminosity-temperature relation for clusters of galaxies is derived. The two models used, take into account the angular momentum acquisition by the proto-structures during their expansion and collapse. The first one is a modification of…
The nature of structure formation around the particle free streaming scale is still far from understood. Many attempts to simulate hot, warm, and cold dark matter cosmologies with a free streaming cutoff have been performed with…
The dark matter halo mass function is a key repository of cosmological information over a wide range of mass scales, from individual galaxies to galaxy clusters. N-body simulations have established that the friends-of-friends (FOF) mass…
The mass function of dark halos in a Lambda-dominated cold dark matter (LambdaCDM) universe is investigated. 529 output files from five runs of N-body simulations are analyzed using the friends-of-friends cluster finding algorithm. All the…
The cosmological mass function problem is analyzed in full detail in the case of 1D gravity, with analytical, semi-analytical and numerical techniques. The extended Press & Schechter theory is improved by detailing the relation between…
We show that DM halos, in n--body simulations, have a boundary layer (BL), separating bound from unbound mass. Let T(r) and W(r) be the kinetic and potential energies in shells of halos. We find that, in almost all halos: (i) The virial…
We study the formation of dark matter halos in the concordance LCDM model over a wide range of redshifts, from z=20 to the present. Our primary focus is the halo mass function, a key probe of cosmology. By performing a large suite of…
We claim that the discrepancy found between theoretical predictions for the cosmic mass function and those found in numerical simulations is due to the fact that in deriving the former all mass elements are assumed to be at the center of…
In this paper, I revisit the constraints obtained by several authors (Reichart et al. 1999; Eke et al. 1998; Henry 2000) on the estimated values of Omegam, n and sigma_8 in the light of recent theoretical developments: 1) new theoretical…
We examine the problem tidally-induced mass loss from collisionless systems such as dark matter haloes. We develop a model for tidal mass loss, based upon the phase space distribution of particles, which accounts for how both tidal and…
This is the first paper of a series of two devoted to develop a practical method to describe the growth history of bound virialized objects in the gravitational instability scenario without resorting to $N$-body simulations. Here we present…
We have constructed the merging history of dark matter halos in a SCDM cosmology, by means of a the {``Merging Cell Model''} (Rodrigues & Thomas 1996). It is based on the linear theory of growth of density fluctuations, and the Top-Hat…
We consider the possibility that dark matter halos are made of quantum particles such as fermions or bosons in the form of Bose-Einstein condensates. In that case, they generically have a "core-halo" structure with a quantum core that…
We take advantage of the biggest cosmological simulation to date for a critical CDM universe in order to test robustness of the cluster mass function on a range of masses much wider than tested before. On the high mass end our results show…
As cosmic structures form, matter density fluctuations collapse gravitationally and baryonic matter is shock-heated and thermalized. We therefore expect a connection between the mean gravitational potential energy density of collapsed…
The halo mass-temperature relation for a sample of 216 galaxy clusters, groups, and individual galaxies observed by $Chandra$ X-ray Observatory is presented. Using accurate spectral measurements of their hot atmospheres, we derive the $M-T$…
We construct a mass or energy function for the non-Nariai class Schwarzschild-de Sitter black hole spacetime in the region between the black hole and the cosmological event horizons. The mass function is local, positive definite, continuous…
We present an empirical method to measure the halo mass function (HMF) of galaxies. We determine the relation between the \hi\ line-width from single-dish observations and the dark matter halo mass ($M_{200}$) inferred from rotation curve…